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By Jake Coibion, Elmira Riahi, Dominic Reda, Walter Klary, Vojtech Gall

Progressive Design-Build is becoming a more common delivery method in the tunneling industry. This approach allows the Owner to select a design-builder primarily based on qualification instead of lowest price. The delivery method promotes flexibility and collaboration at all levels from the initial design stage through construction. Using the example of the Atlanta Airport Plane Train Tunnel West Extension, value-added risk management was added during the initial design phase with an independent reviewer. This paper presents the independent reviewer transitioning from constructability review in the very early stages of design to independent design verification to on-site supervision during construction.

Jun 13, 2023

By L. U. Spellman

Atlantic Cement Company's new multimillion dollar, 10,000,000 barrel per year cement plant went into full operation in February, 1962, bringing into reality a new concept in the distribution of Portland cement. The Cerro and Newmont Mining Corporations, well established in the mineral extraction and dressing industry, backed the venture. To take advantage of the, economics inherent in single production units of large capacity, it was necessary to first find a market' capable of absorbing such large quantities. Cement can be economically shipped by rail and truck about 200 miles. Beyond' that radius from the producing facility the freight costs become prohibitive. No single marker area within that radius exists which could absorb such a large volume of cement. However, water transportation provides a relatively inexpensive method of transporting bulk products many times over such a distance. Thus, it was decided to locate the producing facility near a deep water port which had ready access both to the Atlantic Ocean and, just as important, a good source of raw material. An extensive feasibility study was made and the site at Ravena, New York on the Hudson River near Albany was chosen. Here, vast quantities of limestone in the foothills of the Catskill Mountains are found within a short distance of-the deep-water Hudson River.

Jan 1, 1964

By Edward Keller

About a dozen years ago the art of bessemerizing copper- * matte, brought to these shores from France, was first established at the smelter, in Butte, Montana, of the Parrot Silver and Copper Company, which had bought the process from Mr. Manhks, the inventor. Through the efforts of Mr. J. E. Gaylord, general manager, and Mr. A. J. Schumacher, snperintendent,, assisted by an able staff, the new method rapidly underwent, at the Parrot establishment, an evolution towards higher perfedion, and within a few years its success and its advantages were so marked that all the great works in the west followed in the footsteps of this pioneer. The converter-process has now practically superseded the reverberatory-process in this country. The latter will undoubtedly, in a not very distant future, be relegated to metallurgical history. The writer has availed himself of what was perhaps the last chance to make comparisons of the two methods, working practically on the same material on an extensive scale, the reverberatory process being that of the Baltimore Copper Smelting and Rolling Company,* while the converter-process is that of the Anaconda Copper Company—both using the matte from the latter company's works in Anaconda, Montana. For the greater portion of the material considered in this paper, the writer is indebted to the two companies. In order to understand the difference of behavior of the several elements, and the difference of the copper produced in the two processes, it is best to study and follow those elements

Jan 1, 1899

By J. E. Johnson

The description of the machine which coilstitutes the subject of this paper is best iutroduced by a statement of the conditions which led to its construction, which may be briefly given as follows : The ore handled at the plant to be here described* is of the variety sornetimes called by those familiar with the brown ores of the South, " Mountain," as distinguished from the " Lime-

Jan 1, 1899

By C. W. Bildt

During many years of service in the iron and steel industry I have frequently found, as have also many other engineers, that the common devices used for feeding coal into gas-producers are not what they ought to be in order to secure the best economy. The hopper-and-cone so generally used is familiar to all, and a brief study of its action will surely satisfy everybody that this device has several serious faults. In the first place, the charging is intermittent, and depends entirely upon an attendant. When the hopper is frequently emptied, it may work fairly well, but even then it suddeinly discharges into the hot producers a large body of coal, which is often violently converted into gas that rushes into the furnace, and, as the damper for the combustion-air cannot be regulated every time the producer is charged, there will be an excess of gas, which goes up the chimney unburned. Between the chargings the quantity of gas generated decreases, and there will often be an excess of air in the furnace,

Jan 1, 1899

By R. W. Raymond

Jan 1, 1905

By Edgar S. Cook

Portions of this paper repeat in substance the statements made by me in an address before the meeting of the American Society for Testing Materials, held in June, 1903, at Delaware Water Gap, Pa. The views I then expressed, I still hold and believe to be pertinent to the present discussion of this subject. In doing my part, therefore, at the request of our Secretary, towards the further consideration by the Institute of the Physics of Cast-lron from a commercial as well as a theoretical standpoint,—a theme which received interesting treatment in our meeting some years ago, but has been somewhat neglected recently,—I make no apology for reiterating the views I have expressed elsewhere. Indications all point to the substitution of classifying pig-iron by chemical analysis for the old-time method of grading by fracture. Commencing with the larger users, and the makers of specialties, who require more positive information as to the composition than is afforded by the fracture; the use of pig-iron, guided by analysis, has spread with much greater rapidity to all classes of foundry-work than the most sanguine expected. Grading by fracture, as guided by experience with any particular brand of iron, has some points in its favor. The fact that, for so many years, castings of multitudinous forms, and for an endless variety of uses, were made in a fairly satisfactory

Jan 1, 1905

The Secretary : The work of Mr. A. E. Outerbridge, Jr., of Philadelphia, first made known in his paper on " The Mobility of Molecules of Cast-Iron," read at the Pittsburgh Meeting of the Institute, in February, 1896, has been reviewed by the Committee on Science and the Arts of the Franklin Institute, whose report, dated May 5, 1897, is accompanied with a table of tests made by the Committee, and amply confirming the statements of Mr. Outerbridge. Concerning the originality and novelty of his investigation, the Committee says: " The fact that a certain molecular change takes place in cast-iron in the course of time has been known and recognized by many persons for a long time, and that this change tends to relieve the internal strains and render the casting tougher has often been noticed and acted on, although in a very crude way; but, so far as the sub-committee has been able to learn, Mr. Outerbridge has been the first to make a careful study of this, and to note that the change may be hastened by impact, and the whole effect produced in a short time, and also to make a scientific study of the phenomenon. We believe great credit is due him for the initial observation and the careful work dependent thereon. The results were first given to the public in a paper read before the American Institute of Mining Engineers, on February 20, 1896. This aroused a wide-spread interest and discussion among users of cast-iron, and so far as the sub-committee has been able to determine, it has not been shown that anyone, either in this country or abroad, has antedated Mr. Outerbridge in his work in this line. The Franklin Institute therefore recommends the award to him of the John Scott Legacy Premium and Medal." This report has not been published, hut I have had the opportunity to read it in manuscript. The table of testa accompanying it comprises 91 tests of " rumbled" and an equal number of " not rumbled" companion-bars of cast-iron, 26 by 2 by

Jan 1, 1898

E. D. Peters, Jr., Dorchester, Mass.: This paper of Mr. Keller's seems to me a step in a direction that has been very little exploited, and iff likely to lead to valuable practical re-

Jan 1, 1899

By S. F. Emmons

Jan 1, 1899

By H. M. Howe

The chief purpose of this note is to call attention to the triaxial diagram as a convenient means of illustrating the properties of slags, and by this example of its use to commend it to those inclined to graphical studies having other possible applications. Explanation.—In the common or di-axial diagram, the properties corresponding to any point are determined by its perpendicular distance from each of two axes. For example, in an ordinary stress-strain diagram the properties of a given point in the curve are, first, a stress cd so many pounds per square inch, because its perpendicular distance from the horizontal axis of the diagram corresponds by the vertical scale to that stress; and second, a strain or elongation of so many per cent., because its perpendicular distance from the vertical axis corresponds by the horizontal scale to that elongation. It happens that, as a matter of convenience, we habitually place these two axes at right angles to each other; so that our measurenieilts happen to be made not only at right-angles to

Jan 1, 1899

By Persifor Frazer

The structure of the Caucasus as made out by the Russian geologists and represented in Pamphlet XXII. of the Livret Guide, by Loewinson-Lessing, is an overturned anticlillal from Lars to Passanour; a distorted synclinal with monoclinal dip from Passanour to near the summit of the anti-Caucasus chain south of Tiflis; and another overturned auticlinal from this point to Erivan on the Armenian border. Ng—Neogene; Pg— Paleogene ; J,—Upper Junssic (and Cretaceolls in other parts of the chain) ; J1—Lias ; Pz—Paleozoic schists plicated ; yd—massives of granite and diabase; —porphyries ; —trachytes, andesites; Pz, Mz, plicated sedimentary deposits of Armenia. The details of the geology, however, are extremely complicated—so much so, indeed, as to make it impossible for any set of men to have worked them out in a single season. For 'the structure as a whole it will be necessary, therefore, to rely implicitly upon the labors of the Russian Geological Survey, and it is intended here only to state these, and to record a few notes supplementing them. Setting out from Wladikavkaz in the early morning, we pass

Jan 1, 1899

By James Douglas

I had the good fortune to visit the Stockholm Exposition just before its close in October last, and to get a glimpse of the methods used in Sweden in making the wonderful steel and iron for which its furnaces are so famous. My time and opportunities for observation were limited, but some points which I noted may be worth bringing to the notice of the Institute. The Exposition itself was confined to the natural and artificial products of Scanclinavia, and therefore iron and steel held a very prominent place in it. There was a complete collection of the rocks and ores of the Peninsula made by the Geological Survey; and every iron-mine of note exhibited a glass model of its workings, as well as classified specimens, accompaniecl by thorough analyses of the ores. Another feature of interest was the display of models of the old mining-machinery, in the invention and introduction of which Sweden led the way, and of the old and new surveying-instruments and compasses devised for the exploration of the Swedish iron-ore bodies, all of which are more or less magnetic. The magnetometric collection and exhibit of methods of operation made by Prof. Nordestrijm were supremely instructive. The larger metallurgical works, such as those of the Kopparberg and Sandvik companies, exhibited their wares in separate pavilions, in which crude and manufactured objects were arranged most eflectively and tastefully; while the smaller companies erected in the Industrial Arts Building trophies, every one of which was an object of beauty. One was struck on all sides by the fine asthetic feeling exhibited in the ingenious installation of materials and objects not easily lending themselves to artistic treatment. Hammers, picks and drill-steel were grouped into mural designs which it was a delight to look at.

Jan 1, 1899

By Forbes Rickard

Gilpin County, the cradle of mining in Colorado and the Cornwall of North America, is too well known to need much introduction; get, for the benefit of those not familiar with the district, it may be well to premise that it comprises a tract of country of about 122 square miles, lying between the counties of Jefferson, Boulder and Clear Creek, and hounded on the west by the main range of the Colorado Rockies. It is located centrally in the State, 40 miles west from the city of Denver. During the 38 years since the first gold-discovery, Gilpin county has contributed about eighty million dollars in gold and silver to the world's supply of these metals. Many mining districts have had their rise and decline in half this time; but, very far from being exhausted, this mining district is still in the ascendant; its output is increasing (it was $3,600,000 for the year just closed), and it was never more prosperous nor productive than to-day. Taken generally, there does not exist anywhere in the world so great a number of permanent veins within so small an area as in this district. Gilpin is practically a " poor man's camp." Its veins, with few exceptions, outcrop at the surface. In the oarlier---days of the camp these outcrops were worked in many instances by sluice-mining; particularly is this the case with regard to the veins of the Russell gulch. Discoveries are still made in the heart of this district, and the productive area is every year extending its limits. The districts of Yankee Hill, Hawkeye and Pine Creek, which used to be isolated, are now part and portion of the one gold-field of Gilpin county. Within the last year sensationally rich gold-discoveries have

Jan 1, 1899

By Robert Job

Up to five years ago the pig-iron used by the Philadelphia & Reading Railway Co. had been obtained solely upon the appearance of the fracture; but as the service was unsatisfactory, an investigation was made to determine the quality best adapted

Jan 1, 1905

By Walter Wood

The specifications for cast-iron pipe that have been submitted at this meeting are practically the outgrowth of those which were originally adopted, about 1860, by Mr. Kirkwood of Brooklyn, N. Y. They have been changed but little since that time, the mode of testing pipe in the hydraulic press, as well as the method of coating, not having departed from the original practice. The chief addition to the specifications has been in the adoption of a test-bar 2 in. by 1 in. in crosa-section, broken between 24-in. supports by a transverse strain applied on the flat side. Test-bars were first introduced into pipe-specifications about 1870. At that time a satisfactory test-piece had to stand a tensile strain of 16,000 lb. per square inch. The present test-bar was adopted in order to give some idea of the deflection of the iron that was being used. These deflection-tests have been so satisfactory to both engineers and manufacturers, and have met the requirements of the pipe-trade so accurately, that it is considered best to hold to the . 2-in. by 1-in. bar instead of adopting the short " Arbitration Bar," which yields but little information from the stand-point of deflection. The new feature in these specifications is the effort to reach standards to which pipe shall be cast in the future, thus permitting the manufacturer to make up stock and the purchaser to find material on hand when he asks for deliveries. Heretofore there has never been ally standard weight for pipes? although in some sizes certain weights are more frequently asked for than others. The fixing of standards for pipes permits the adoption of definite standards for fittings. It has been aimed to secure such uniformity for fittings as will permit the same class of fittings to cover two or more classes of pipe. In order to accomplish

Jan 1, 1905

The following specifications, proposed by a sub-committee of the American Society for Testing Materials, are still to be adopted and subsequently submitted to the International Association for Testing Materials. Standard Specifications for Pig-Iron and Castings. I. Analysis.—It is recommended that all purchases be made by analysis. II. Sampling.—In contracts where pig-iron is sold by chemical analysis, each carload, or its equivalent, shall be considered as a unit. At least one pig shall be selected at random from each two tons of every carload, and so as to fairly represent it. Drillings shall be taken so as to fairly represent the fracture surface of each pig, and the sample analyzed shall consist of an equal quantity of drillings from each pig, well mixed and ground before analysis. III. Allowances and Penalties.—III all contracts, in the absence of a definite understanding to the contrary, a variation of 10 per cent. of silicon, either way, and of .01 in sulphur above the standard is allowed. A deficiency of over 10 per cent. in the silicon, up to 20 per cent., and a further increase in sulphur up to .01 over the above allowance subjects the shipment to a penalty of 1 per cent. in the price for each element so affected. IV. Base Analysis OF Grades. —In the absence of specifications the following numbers, known to the trade, shall represent the appended analyses for standard grades of foundry pig-iron, irrespective of the fracture, and subject to allowances and penalties as above. Silicon Sulphur Grade. Per Cent. Per Cent. No. 1,...2.75 0.035 No. 2,.2.25 0.045 No. 3,........1.75 0.055 No. 4,.1.25 0.066 Cast-Iron Pipe and Special Castings. I. Description of Pipes.—The pipes shall be made with hub- and spigot-joints, and shall accurately conform to the dimensions given in Tables Nos. I. and 11. They shall be straight and shall be true circles in section, with their inner and outer surfaces concentric, and shall be of the specified dimeneions in outside diameter. They shall be at least 12 feet in length, exclusive of socket. For pipes of each size from 4-inch to 24-inch, inclusive, there shall be two standards of outside diameter, and for pipes from 30-inch to 60-inch, inclusive, there shall be four standards of outside diameter, as shown by Table No. 11.

Jan 1, 1905

By Theodor Knutzen, Charles H. Fulton

The plant of the National Smelting Co., a corporation controlled by the Horseshoe Mining Co., was built during 1901 to smelt the dry siliceous ores of the northern Black Hills, extracting the gold- and silver-values in a matte of low copper-percentage which is shipped to Omaha and Denver for refining. Originally, the plant was designed to collect the values of the siliceous ores in an iron-matte, which mas to be resmelted with lead-ores, in a lead-furnace, the lead-bullion produced to be refined into Doré bullion in English cupelling-furnaces. However, the scarcity of lead-silver ores in the Black Hills, owing to the present non-productiveness of the Galena district, led to

Jan 1, 1905

By René de Batz

From 1754 to the end of 1895 the production of gold in Russia had been approximately as follows: Kilogrammes. Russia proper (Finland and the Caucasus),. .. 890 The Ural Region,........505,386 Western Siberia,........116,937 Eastern Siberia,........1,218,372 Total,.........1,841,085 of the value of more than $1,200,000,000.

Jan 1, 1899

By Charles H. White

+1HARVARD UNIVERSITY, CAMBRIDGE, MASS. The equipment of a laboratory in which students are to be trained for practical work in metallurgical chemistry presents many difficulties not encountered in the fitting up of a commercial or works laboratory. At an industrial plant the chemical work required usually demands the frequent repetition of a comparatively limited number of methods. In a steel-works laboratory, for instance, by far the larger part of the work consists in making determinations of the usual impurities found in iron and steel; at a smelter the great bulk of the work is confined to the analysis of ores, slags, mattes, and fuels, which involve the frequent application of perhaps not more than a dozen different methods. In a laboratory of this character, therefore, those operations most frequently applied may each have a certain section set apart and fitted permanently with such apparatus as best facilitates the carrying out of this one operation. The work of a commercial or custom laboratory is perhaps more varied than that of a works laboratory, but the couditions are similar in these respects, that there is usually no great need for economy of space, and that a few skilled workmen are employed to carry the determinations through from beginning to end without interruption. On the other hand, the laboratory of a technical school should be planned on such a scale that a comparatively large number of students may work at the same time, and each desk should be equipped for general metallurgical analysis. In most institutions for technical education the student's program is so arranged that his day is divided among several subjects in the course of study; only a few consecutive hours being devoted to one subject, or spent in one laboratory. Therefore, those appliances should be provided that render possible the safe continuation of such processes as

Jan 1, 1905